Are there replays of bad (new) players with commentary?
TotalBiscuit has a series called I Suck at Starcraft where he comments on his own noob games, focusing on what mistakes were made and how to improve.
The series starts out very basic, explaining economy, supply, teching, and the uses of some individual units. It should be understandable even for someone brand-new to SC2. The downside to this is that it may be too basic for many players. However, over the course of about 15 videos, he moves into (somewhat) more advanced concepts.
As mentioned by Ivo Flipse, Day9 has done a few casts of inexperienced players. These are the ones I could dig up (a couple casts were during the beta, so some things may be out of date, but the main ideas are still there):
Day[9] Daily #115 - A Fun 2v2 of My Housemates
Let's take a break from the usual analysis to admire the beauty of Starcraft 2: the game can create epic matches between players of all skill levels. In #115, we get the chance to watch a game between players I live with! I got the chance to see this game happen live, and it was quite a treat to see :D
Day[9] Daily #121 - Plugging Leaks in Silver Level Play
In this episode, we examine a silver and gold level players to point out some classic leaks of inexperienced regulars.
Day[9] Daily #146 - Gold Level 2v2 Analysis
For anyone looking for silver and gold level 2v2 strategy, this is a must watch. I look at a replay from some very average players and discuss general strategy for 2v2 play.
Day[9] Daily #163 - Gold Level: Fixing the Little Things
In this episode, we take another look at Gold and Platinum level play and how to really improve, what to think about during the game, how to watch your own replays to improve, and other basic topics to help you be a better gamer.
Day[9] Daily #164 - Low Level Reps - In-game Decision Making
This time, we examine the importance of going into a game with a plan, especially for lower level players. We talk about a players starting plan, we see how it does and look at how to change your plan in the middle of the game when it's necessary. We also really look at the little things that are important that non-diamond players often forget.
Day[9] Daily #208 - Live coaching with djWHEAT (this one is very interesting)
We'll be doing a live coaching session w/ DJWheat direct from Phoenix Arizona where we'll help try to find some of Wheat's leaks and point out how to be thinking during a ladder match.
After Dave Andersen made his post, Day[9] started a new weekly event called Newbie Tuesday, where he does exactly what we're looking for: every week, he goes over a silver/gold/platinum level game and explains what they did wrong.
I'll keep a list of them here as they come out.
Day[9] Daily #184 - Newbie Tuesday #1
This is the first in the series of Tuesday episodes dedicated to players below the Diamond level. Day[9] examines the common mistakes of Bronze through Platinum level players, shows what to focus on and what not to really worry about until you're a top Diamond player. This particular episode is a PvT, although the concepts apply to all races.
Day[9] Daily #189 - Newbie Tuesday: Losing to Early Pressure
In this Newbie Tuesday special, we examine how to avoid losing to early aggression in a variety of matchups.
Day[9] Daily #194 - Newbie Tuesday: Drone Timing
In this Newbie Tuesday episode, we focus on the timing of making Drones as a Zerg player. Specifically, how to figure out if it you need to make an army or build your economy at any given time. We look at using scouting info, harassment, and defensive strategies to optimize your economy while not actually dying.
Day[9] Daily #198 - Newbie Tuesday: Banshee Harass
In this episode of Newbie Tuesday, we address the common problem of being harassed by Banshees at different stages of the game.
Day[9] Daily #201 - Newbie Tuesday: Using Drops
In this episode, we look at how to effectively use drops to gain an advantage, and point out common mistakes.
Day[9] Daily #205 - Newbie Tuesday: Dealing with Colossi
In this Newbie Tuesday, we focus on what the different races can do when faced against the mighty Colossus!
Day[9] Daily #210 - Newbie Tuesday: 2v2 Strategy
This time, we'll take a look at early game 2v2 and see why people lose to rushes so much! We really examine the rush as a valid strategy, and look at how to cope with them and still win!